In resin-molded semiconductor devices, adhesive tapes are now mainly used as the adhesives for bonding semiconductor elements (chips) to lead frames.
If the adhesive tapes used for the above purpose contain contaminants or defects, the reliability of semiconductor devices may be lowered. It is therefore necessary to inspect adhesive tapes for contaminants and defects before applying the adhesive tapes to adherend lead frames, to avoid using adhesive tapes containing contaminants or defects.
A conventional, simple method of removing contaminants is to cut off the parts containing contaminants from adhesive tapes, to obtain contaminants free adhesive tapes. This method however requires many hands and is inefficient.
According to an alternative for preventing contamination, the regions containing contaminants are marked with seals, ink or the like, to avoid these regions and use other regions for bonding. This method also needs improvement since the adhesive tapes may be contaminated by the marking, causing the contamination of adherend chips.